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57 Ways To Protect Your Home Environment (and Yourself)
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42. Test Your Home For Radon

radon sources diagram

Radon is created naturally in the earth—a tasteless, colorless, and odorless gas that forms when uranium in the Earth’s soil decays. As radon decays, alpha particles are emitted, which can damage cells in the human body. Some scientists claim that radon gas is responsible for 7,000 to 30,000 lung cancer deaths per year, but other scientists dispute this figure, saying it exaggerates the risk.

Outdoors, radon gas is diluted in the air and poses little risk. But indoors it can become concentrated and can accumulate to hazardous levels. Radon can enter through crawl spaces; gaps between basement floors and walls; sump pumps; and the water supply.

radon sources diagram

It can also enter through cracks in basement walls, floors, and foundations; pores in concrete block; mortar joints; and openings around loosely fitted pipes.
radon testing

There are two basic types of radon detectors. Short-term detectors, such as charcoal canisters, measure radon levels over a two- to seven-day period. Radon levels within a home fluctuate with the weather, so these tests can be deceiving. Long-term detectors, such as alpha-track detectors, measure radon levels for three months to a year.
radon testing kit

You can purchase radon testing kits rather cheaply from a local hardware store or other retail outlets. Their price usually includes the cost of having a laboratory analyze the detector and report the findings. Whatever kind of detector you choose, make sure that the package indicates that the test kit meets EPA requirements.
radon detection kit

Radon detection kits should come with thorough instructions on how to set up the test. Be sure to indicate the dates that you begin and complete the test. Also, mail the detector to the lab immediately after completing the test. Not doing so may result in a failed test.
radon testing

Here are some testing steps: Do a short-term test or long-term test (the U.S. EPA recommends starting with a short-term test). If your long-term test exceeds 4 picoCuries per liter of air (pCi/L), that is sufficient reason to take action to reduce radon levels in your home. If your short-term test result is 4 pCi/L or higher, you should do a follow-up test to be sure.
radon testing

Follow up with either a long-term test or, if you need quick results, a second short-term test. Take action to solve the problem if the follow-up test is 4pCi/L or more.

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